The new versions of BCC and RED are fully compatible with Mac OS 10.6+, which includes Snow Leopard and Lion.
We just released BCC 8 AVX 64 bit, which requires the recently released Avid MC 6 64 bit host as it's a 64 bit plug-in and can't run in a 32 bit host environment. We will be making a 32 bit version of BCC 8 available very soon, which can be used in 32 bit versions of Avid MC, such as MC 5x.
And I have the reverse question regarding Boris Red. I get the impression it does not integrate with Avid 6. Am I wrong? If so, where do I find the Boris FX effect within Avid 6? If I'm correct that it isn't there, will it be at some point?